Work-experience schoolboy discovers a new planet

 

An artist’s impression of the planet, WASP-142b, orbiting its star, WASP-142. The planet is depicted as seen from a hypothetical moon. A second, dimmer star is seen in the background. Being 1000 light years away, the planet is too distant to obtain a direct image. Source: Keele University

A 15-yr-old schoolboy has discovered a new planet orbiting a star 1000 light years away in our galaxy. Tom Wagg was doing work-experience at Keele University when he spotted the planet by finding a tiny dip in the light of a star as a planet passed in front of it.

“I’m hugely excited to have a found a new planet, and I’m very impressed that we can find them so far away”, says Tom, now aged 17. It has taken two years of further observations to prove that Tom’s discovery really is a planet.

Tom found the planet by looking at data collected by the WASP (Wide Angle Search for Planets) project, which surveys the night skies monitoring millions of stars to look for the tell-tale tiny dips (transits) caused by planets passing in front of their host star.

Tom’s planet has been given the catalogue number WASP-142b, being the 142nd discovery by the WASP collaboration. It is in the Southern constellation of Hydra.

The planet is the same size as Jupiter, but orbits its star in only two days. The hemisphere facing the star is hot, blasted by the irradiation from the star, while the other hemisphere is much cooler. With such a short orbital period the transits occur frequently, making such planets much easier to find.

The planet is one of a class of “hot Jupiter” planets, which – unlike the planets in our own Solar System – have very tight orbits close to their stars. They are thought to have migrated inwards through interactions with another planet. Thus it is likely that Tom’s planet is not the only planet orbiting that star.

The WASP collaboration (Wide Angle Search for Planets) is the UK’s leading team discovering planets, having been recognised with a Group Achievement Award by the Royal Astronomical Society. Keele University operates WASP-South, an array of cameras which surveys the Southern Hemisphere sky each clear night.

After Tom found the candidate planet, it was studied by astronomers at the University of Geneva and the University of Liege, to prove that it has the right size and mass to be a planet. A paper reporting an analysis of WASP-142b is being prepared.